This is an introduction of texturing a human face. It is for
those who does not know how to get started on texturing. In this tutorial,
I will explain the basics on how to merge, colour correct and touch ups of
a set of photos into a useable texture for 3D polygon face. You must have
basic knowledge of photoshops.

I have a simple polygon face which is only around 1000 triangles. I did it
in XSI but this tutorial mostly will focus on photoshop. It should able to
apply on any 3D softwares.

To create a relistic face texture. A set of high resolution image is the
most important facter in this task. Tobe the best is to have different section
and different angles of faces. (This ugly guy's face is my face. It is less
time consuming if I take photo references of myself rather than searching
on the web.)

Lets start making a face texture. Create a new document in photoshop. I set
the ratio as 20:17 mostly. Click OK. Paint the white background(or whatever
colour your background is) to 75% gray. With this background colour which
can easily isolate the rest of the layer visually when you are working along.

I chose 3 shots in different angles. Layer them in order. I am going to merge
them together. To erase the area which youdon't want, please do not use the"eraser
tool". Make a "layer mask" on each layer to paint away the
unwanted area instead.

Tip: If you don't
know how to add a layer mask. Select each layer individually. Click on the
button "add layer mask" in the very bottom of the layer window.
By default the layer mask is white. Select the brush tool, choose colour "100%
black" to paint away all the unwant area. If you made a mistake, all
you have to do is to select "100% white" and paint again on its
mistaken surface.

Remove unwanted area and colour adjust them tobe the same. Merge(ctrl-e,
or ctrl-alt-e) the 3 layers (you may or may not keep a copy of the unmerged
version, I do not keep them usually).

Colour adjust the layers using "Level"(ctrl-l) and "Saturation"(ctrl-u).
Since I took this images around a greeny room so the white balance of the
camera added alot of blue into my face. I have to add more yellow and red
to it. Lighten the whole layer about 20% as well.

Add a new layer on top. Use the dropper(hold "alt" then left click)
to pick a general skin colour(set your dropper to 5 by 5 average). Set your
brush as air brush: opacity 100%(as always), flow 15-30%. Paint around the
face wherever you see the face is too dark, too greeny, or too bluey. The
idea is to average it out so it looks like they are merged. Set your layer
blend mode as "softlight". Add another new layer on top but set
it as "darken", pick the same colour but this time is to paint on
the highlight. You do not want any highlight or shadow showing in a colour
map. Make the texture as flat as possible but mainwhile do not remove any
detail.

Use the same idea to paste and merge every section of the face.

Added layer mask and remove hard edges. Colour corrected to match the previous
sections. Next is to clone and heal the rest of the head and neck.

I should take more photo reference for the forehead and around the neck.
However in this tutorial I only clone around. The more photo reference you
have, the more relistic detail you will get. Now, lets map to the mesh and
see how it looks. I asume all of you knowing how to UV unwrap.

DADA!!! It is simple isn't it. However it can be more complicate if you want
every single detail tobe showing. The method is the same. Get more photo references
in every single part of the face. Get attention to detail.

PS: Keep in mind that if you are making a high resolution face, do not keep
or paint any shadings or highlights onto the colour map. Since your mesh will
generate shadows and you'll have a spec map for highlights. In the other hand
in low res face, you must paint more shadings and highlights or even different
skin colour to accenduate different parts of the it. To paint shadings, do
not use a single colour tone for the whole head. More often to use "dark
blue", "dark green", and "brown". Isolate every colour
in differen layers. Change differen blend mode to see which blend method will
give the best effect.